Sealing device for joint section of robot and articulated robot having the same

Abstract

A sealing device provided to a joint section of a robot. The sealing device includes overlapped seal portions having a multi-stage configuration, provided for a driving mechanism incorporated into the joint section. The overlapped seal portions include a first seal portion including a first contact seal element sealing a first inter-member gap defined adjacent to a lubricant retaining section provided in the driving mechanism; and a second seal portion arranged outside the first seal portion and including a second contact seal element sealing a second inter-member gap defined in a circumferential wall of the joint section, the circumferential wall defining an accommodation space for accommodating the driving mechanism.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a sealing device provided to a joint section of a robot. The present invention also relates to an articulated robot in which a joint section is equipped with a sealing device.[0003]2. Description of the Related Art[0004]Typically, in an articulated robot in which a driving mechanism for driving an arm or a wrist is incorporated into a joint section, in order to prevent a lubricant retained in the driving mechanism from leaking out, to the exterior of the joint section, an oil seal, as one type of a contact seal element, is provided in a relatively movable region of an output-end member of the driving mechanism (e.g., a bearing unit at the output side of a reduction gear unit). In particular, in certain applications where it is required to effectively prevent the environment of the robot or an objective workpiece to be operated by the robot from being contaminated due to the operation of ...

AI Technical Summary

Benefits of technology

[0008]It is an object of the present invention to provide a high-performance sealing device provided to a joint section of a robot, which can reliably prevent a lubricant or dust particles, retained or generated in a driving mechanism incorporated into the joint section, from leaking out, to the exterior of the joint section, and also prevent foreign matter in the external environment of the robot from penetrating into the interior of the joint section.

[0009]It is another object of the present invention to provide an articulated robot provided with a high-performance sealing device in a joint section, wherein the sealing device can reliably prevent a lubricant or dust particles, retained or generated in a driving mechanism incorporated into the joint section, from leaking out, to the exterior of the joint section, and also prevent foreign matter in the external environment of the robot from penetrating into the interior of the joint section, so that the articulated robot can be preferably used on manufacturing lines in which products are required to be free from contamination.

Problems solved by technology

However, if the lubricant in the driving mechanism passes through the grease seal, forming the inner seal portion of the overlapped seal portions, the above conventional sealing device may not sufficiently seal in the lubricant.

Further, since it is assumed that, in JP-A-63-22290, the robot is used in a clean room, in the case where foreign matter, such as dust particles, liquid droplets, etc., exist in the external environment of the robot, it may be difficult to prevent the foreign matter from penetrating through the labyrinth seal into the wrist housing.

Therefore, in the case of the articulated robot for handling products required to be free from contamination, even if the joint section is equipped with the sealing device described in JP-A-63-22290, it may be difficult to ensure sealing at a required level.

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